Biology Guide Cell Cycle
Compare an d contras t the role of cel l divisi on in unicel lular and mu ltice llular organisms.In a unicellular organism, cell division creates an entire new organism, but in multicellular organisms, it creates offspring. Additionally, in multicellular organisms, cell division enables sexually producing organisms to develop from a single cell (zygote), and it can also allow renewal and repair of cells. Def ine the fol low ing ter ms: a. Gen ome: A cell ’s gen eti c inf orma tio n. Chromo somes: DNA mo lecules are pac kaged i nside of he re. Somat ic cel ls: A ll bo dy cel ls exc ept f or repr oductiv e cell s. Gam ete s: rep rodu cti ve cel ls.
Chroma tin: Th ey make up e ukaryo tic chrom osomes; they are a c omplex o f DNA and protein molecules. Sister chromat ids: A dupl icated chromos ome is made u p to t wo ch romati ds that are exactly alike, thus the name sister chromatids. Centro mere: Th e point a t which t wo chrom atids me et to fo rm a chrom osome. Mit osi s: Th e div isi on of t he nu cle us. Cyt oki nesi s: The div isi on o f t he c yt opl asm. Meiosis: A cell division in which gametes are formed. Lis t the a cti vit ies of the c ell c yc le: a.
BIOLOGY THE CELL CYCLE STUDY GUIDE ANSWERS ap biology vocabulary list this is a list of terms that you should be able to definedescribe a good rule.
Mito tic phas e: The p hase in which the nuc leus un dergoes divisi on. Interp hase: Th e part of t he cell cy cle in whi ch the cel l grows, copies it s DNA, and copies organelles. G1 phas e: The first stage o f inte rphase i n whi ch the c ell gro ws. G2 phase: The thir d stage of interp hase in w hich the ce ll copi es the organelles and finishes its growth.
S phase: The secon d phase of interp hase in w hich the ce ll copi es its DN A for when mitosis occurs. Def ine the fol low ing ter ms: a. Mito tic spin dle: I t forms i n the cyt oplasm dur ing prop hase and it pulls t he chromosmes apart. Centro some: Th is an organel le that ass embles t he microt ubule spi ndle fib ers.
Microt ubule or ganizi ng cent er: Par t of ce ntrosom e that organize s the microtubule spindle fibers. Aster: an array of s hort mi crotubu les that extend s from eac h centro some. Kinet ochore: a s tructu re of prot eins ass ociat ed with sp ecifi c secti ons of chromosomal DNA at the centromere.
Descri be the experi ment conc erning t he moveme nt of microt ubules dur ing mito sis and its results.During interphase, the centromere replicates to make two centromeres and they move apart inside of prophase and prometaphase. Inside of metaphase, asters, short microtubules, form and extend from the centrosomes. Kinetochores of chromosomes and microtubules attach, making kinetochore microtubules, which will allow for the sister chromatids to be pulled apart from eachother. Contra st cy tokines is i n pla nt a nd ani mal cells.Inside of animal cells, cytokenisis occurs by cleavage. Cleavage is first apparent because of a cleavage furrow, which is a groove on the old metaphase plate. Microfilaments allow the cleavage furrow to pinch and open, creating two separated cells.
Biology 1 Review Guide Cell Cycle
However, plants have a cell wall so the process is different. There is no cleavage furrow, so instead du ring telophase, vesicles from the golgi apparatus move along the microtubules and form a cell plate, which enlarges and surrounds the membrane, and separates the two daughter cells by coming in between them. De fi ne b in ary f is si on.Binary fission is a cell division that prokaryotic cells undergo. The DNA begins to replicate in an area called the origin of replication, therefore, making two origins of replication. When the chromosomes are replicating, the cell elongates to about twice its original size, and the plasma membrane move inward, dividing the cell into two daughter cells. Discus s the hypot hetica l evo lution of mi tosis.It is said that two of the proteins involved in binary fission are related to eukaryotic tubulin and actin proteins.
As eukaryotes evolved, binary fission must have given rise to mitosis. Also, two types of nuclear division in certain unicellular organisms have been unchanged over evolutionary time. In both of these cases, the nuclear membrane is intact.
What is t he cell cy cle contr ol syst em and how d o checkpo ints pl ay into t his? -The cell control system is a cyclically operating set of molecules in the cell that both triggers and makes major events inside of the cell. Checkpoints are related to this because they are the parts of the cell cycle control system that check if the processes in the previous steps were done correctly so that the next step can continue. What is a cyclin and what does it activate? -Cyclin is a protein whose concentration fluctuates cyclically (highest during mitosis).
What are Cdk ’s? -Cdk is a cyclin dependent kinase, which is only active when it is attached to a cyclin. What does MPF stand for and what does it promote? -MPF stands for Mitosis promoting factor. It promotes mitosis.
What is a growth factor? -A growth factor is a protein released by certain cells that stimulates other cells to divide. It is an external signal. What is density-dependent inhibition? -It is an external signal.
It is when cells stop dividing when they are crowded and cover a certain surface. 15.What is anchorage dependence? -It is also an external factor. It is when cells divide when they are attached to a certain substance, such as when a rock candy hardens onto a string. Define the following terms: a. Tr an sf or ma ti on -The process that converts a normal cell into a cancer cell. Be ni gn t um or -A tumor that is caused by abnormal cells remaining in the original site; a lump.
Figure%: The Cell Cycle The cell cycle is the recurring sequence of events that includes the duplication of a cell's contents and its subsequent division. This SparkNote will focus on following the major events of the cell cycle as well as the processes that regulate its action. In this and the following SparkNotes on cell reproduction, we will see how the cell cycle is an essential process for all living organisms.
In single-cell organisms, each round of the cell cycle leads to the production of an entirely new organism. Other organisms require multiple rounds of cell division to create a new individual. In humans and other higher-order animals, cell death and growth are constant processes and the cell cycle is necessary for maintaining appropriate cellular conditions.
As we discussed in the, the goal of cellular reproduction is to create new cells. The cell cycle is the means by which this goal is accomplished.
While its duration and certain specific components vary from species to species, the cell cycle has a number of universal trends. DNA packaged into chromosomes must be replicated. The copied contents of the cell must migrate to opposite ends of the cell. The cell must physically split into two separate cells.
We will discuss the general organization of the cell cycle by reviewing its two major phases: M Phase (for mitosis) and interphase. Interphase is generally split into three distinct phases including one for DNA replication. We will finish with a discussion of the elements that control a cell's passage through these various stages. The cell cycle is very highly regulated to prevent constant cell division and only allows cell that have met certain requirements to engage in cell division.